What is sub-customer management in a PBX?

What multi-tenant means

"Tenant" means a resident who rents a home. A multi-tenant system is one system in which many tenants live, each in their own apartment. It's like a building: the foundations, elevator and plumbing are shared, but every family has a locked door, its own key and quiet from the neighbors.

In a cloud PBX, the building is the infrastructure: the servers, the connections to the telephone network, the backups. The apartments are the customers. Each customer has its own numbers, extensions, menus, call log and users, and sees nothing belonging to any other customer.

This is really what makes a virtual PBX possible: instead of every business having its own server, everyone enjoys one large, backed-up infrastructure, and each one gets a PBX that is completely private from its own point of view.

How it's built: layers of accounts

In these systems, accounts are arranged like a tree. At the top is whoever operates the infrastructure. Below it there can be resellers, and below each reseller, its customers. Sometimes there is another level too: a customer with several branches or institutions beneath it.

• Permissions flow downward. A reseller sees its own customers, but not another reseller's. A customer sees only itself.
• Separate settings. Each customer sets its own business hours, queues and menus without affecting anyone else.
• Separate billing. Each account has its own balance, credit limit and invoices.
• Separate users. Each customer can have several users with different permissions: a manager, a secretary, an agent.

Who It's For

• Resellers: communications installers, IT consultants or service providers who sell phone systems to their customers and manage them.
• Chains with branches: stores, clinics or organization branches, each managed separately, but management wants an overall picture.
• An organization with institutions under it: for example, an organization that runs several yeshivas, Talmud Torahs and a nonprofit, where each institution has its own lines, office and account.
• Management companies: which manage the telephony of several small businesses on their behalf.

What a reseller needs from the system

A reseller who manages dozens of customers can't log in to each one separately with a different username and password. They need one screen that shows all the customers, a quick search, and the ability to "enter" a customer's account and see exactly what the customer sees, so they can fix a problem, change a menu or add an extension while the customer is on the line.

The other side is money. A reseller needs to know how much each customer uses, set limits for them and issue them an invoice:

• Balance: how much is left in the customer's account, or how much they owe.
• Credit limit: how far a customer is allowed to run up a debt before service stops. A limit like this protects the reseller from surprises, for example after a breach that generates expensive calls.
• Invoices: orderly issuing for each customer, without calculating manually from call logs.

Advantages and Limitations

Advantages: one backed-up infrastructure for everyone, fast setup of a new customer, centralized management, and full privacy between customers. For a small customer, it provides a PBX at the level of a large organization, without having to keep a server.

Limitations: the separation has to be absolute. A mistake in permissions could expose one customer's information to another. So it's important to give access only to those who need it, and to check from time to time who the users are at each level. In addition, a change at the reseller level can affect all the customers beneath it, so you work carefully.

Tips for resellers

• Give each customer its own user, and don't share the reseller's user.
• Set a reasonable credit limit for each customer at setup.
• Go over the balances once a month, before issuing invoices.
• Document what is different for each customer and when. It saves hours when a question comes in.

A day in the life of a reseller

This is what an ordinary morning looks like for a communications installer who manages his customers' telephony from one control panel:

• 8:30, the customers screen. A list of all the customers in one place, with search. One glance is enough to see who is new, who hasn't been active, and who is close to their credit limit.
• 8:45, a call from a customer. "The menu isn't working." The reseller enters the customer's account (the same screens the customer sees), opens the call flow, and sees that the business hours group is still on winter time. A one-minute fix, while the customer is on the line.
• 9:30, a new customer. They set up an account: a number, extensions, a menu, and set a credit limit right from the start. They exit the account and go back to the list.
• 11:00, balances. A scan of the balances: one customer is close to their limit. A short call to them before the service stops, not after.
• End of the month, invoices. They issue an invoice for each customer from the control panel, without calculating manually from call logs.

The important point: the reseller never asks the customer for a password, and never logs in "as" the customer. They have their own login, and the system knows it's them who signed in.

Full example: a reseller with twenty customers

An IT consultant from Bnei Brak who also provides telephony. Twenty customers: eleven small businesses (2 to 6 extensions each), three medium offices (10 to 20 extensions), two yeshivas, two nonprofits, a clinic and a gemach (free-loan fund). In total about 160 extensions and 35 numbers.

The structure. Each customer is a separate account with its own users. The medium offices have two users each: a manager and a secretary. The yeshivas have the manager only. No customer sees any other, and the reseller sees them all.

The limits. For the small businesses, a low limit, because their usage is predictable. For offices that dial abroad, a higher limit, but not without a ceiling: if one day expensive, unexpected calls appear, the limit is what stops the damage. For nonprofits, a limit adjusted to a campaign month, lowered afterward.

A typical week. Two or three customer requests: a menu to change, an extension to add, an agent who isn't joining the queue. Each request means entering the account, fixing, and exiting. One to two hours a week, with no travel.

End of the month. One hour: going over the balances, updating the limit for two customers who grew, and issuing twenty invoices. Two years ago, with twenty customers on physical PBXs, the same end of month was a full day of collecting data from twenty places.

What happened when a customer left. One business closed. The reseller canceled the users, kept the number for a transition period with an announcement, and released it afterward. The other nineteen customers felt nothing.

Credit limit and balance: how it works in practice

The balance is a single number for each customer: how much money is in their favor, or how much they owe. Every outgoing call that costs money, every SMS and every monthly service changes it. The limit is the boundary: how much debt is allowed before the system stops paid services.

Two models are common worldwide: prepaid, where the customer loads an amount and calls are deducted from it, suitable for a new customer or one who is hard to collect from; and on credit, where the customer uses the service and pays at the end of the month, and the limit protects the reseller. Many resellers start a new customer on the first model and move to the second after a few months of orderly payments.

What do you do when a customer approaches the limit? You call them. Almost always there is a simple reason, such as a busy month or a new agent who dials abroad a lot, and the limit can be raised with a click. Sometimes the reason isn't simple, and then the limit did exactly its job.

What's separate and what's shared

The left column is the reason the price per small customer is reasonable; the right one is the reason they don't see the neighbor.

Mistakes new resellers make

• A customer without a limit. "He's a good customer, he doesn't need one." A limit isn't a lack of trust. It's insurance for both of you.
• One user for all the customers of the same owner. Two businesses of the same person are still two accounts. When he sells one of them, you'll be glad you separated them.
• A change in the wrong account. You enter a customer's account, deal with a different call, and go back to the screen without checking whose account you're in. Before every save, look at the customer's name at the top of the screen.
• Not documenting. After a year there are twenty customers and a hundred small changes that nobody remembers. One line in a file for each change: date, customer, what.
• The customer doesn't know how to log in by themselves. From day one, give them their own user and show them the basic screens and the guides. A customer who handles the small things alone leaves you with the big ones.

The same idea without a reseller: an organization with several institutions

This structure isn't reserved for those who sell telephony. An organization that runs a yeshiva, a Talmud Torah and a charity nonprofit can work exactly this way: the head office at the top level, and each institution with its own account.

What does this give? The yeshiva's office manages its menu and its parents' line without seeing the nonprofit's donations line. The organization's treasurer sees all three accounts and the balance of each, and issues a separate invoice for each institution, because each institution has its own books. And when a fourth institution opens, an account is set up for it the same day, with permissions only for its own people.

The only difference from a reseller is who pays: here everything stays inside the same organization. The separation, the entry into each account and the overall picture at the top are identical.